问题描述
有没有使用在一次查询时mediastore数据的方法?
is there any method to use join in a query at mediastore data?
或者也有没有通过数据库和不访问mediastore数据与内容提供商的方法?
Or also is there any method to access the mediastore data through a database and not with the content provider?
感谢你。
推荐答案
不过,我认为,你可以使用连接与内容提供商。如果你把两个查询,您可以通过使用CursorJoiner加入他们的行列。我用它和它的作品很好。
But I think that you can use joins with content providers. If you make two queries, you can join them by using CursorJoiner. I am using it and it works good.
片段从Android的文档:
Snippet from Android docs:
CursorJoiner joiner = new CursorJoiner(cursorA, keyColumnsofA, cursorB, keyColumnsofB);
for (CursorJointer.Result joinerResult : joiner) {
switch (joinerResult) {
case LEFT:
// handle case where a row in cursorA is unique
break;
case RIGHT:
// handle case where a row in cursorB is unique
break;
case BOTH:
// handle case where a row with the same key is in both cursors
break;
}
}
这是不完全的SQL连接相同,但它是有用的。在每一个案例,你可以用两个光标这是指向处理过的行处理。
it is not exactly the same as SQL join but its useful. In each "case" you can manipulate with both cursors which are pointing to processed row.
这篇关于Android的我可以使用JOIN在mediastore查询的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!